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Fatih Duman - One of the best experts on this subject based on the ideXlab platform.

  • biosynthesis of silver nanoparticles using leaf extract of Aesculus hippocastanum horse chestnut evaluation of their antibacterial antioxidant and drug release system activities
    Materials Science and Engineering: C, 2020
    Co-Authors: Fatma Ozturk Kup, Seval Coskuncay, Fatih Duman
    Abstract:

    Abstract Biosynthesis of metal nanoparticles is expected as a cost efficient and ecofriendly option in the research study. Therefore, the aqueous extracts made from leaf of Aesculus hippocastanum (horse chestnut) were used as the reducing factors to synthesize silver nanoparticles (AgNPs) and their antioxidant, antibacterial and the application of resveratrol combined AgNPs as efficient delivery vehicles have also been evaluated. The biosynthesized AgNPs were characterized by UV–Visible Spectroscopy, Fourier-Transform Infrared Spectroscopy (FTIR), X Ray Diffraction (XRD), Zeta potential, and Scanning Electron Microscopy (SEM). The AgNPs were found to be stable at −29.1 mV through zeta potential study. According to the UV-Vis measurements, AgNP formation was observed at a wavelength range of 420–470 nm. The Ag NPs were spherical with a size of 50 ± 5 nm. AgNPs exhibited strong antibacterial activity against all tested bacterial species but have no effect against fungal strains. AgNPs showed an important inhibitive activity counter the DPPH radical and thereby indicate a source for antioxidants. The free radical scavenging activity of AgNP was calculated as 54.72% at the highest concentration (100 ppm). The superoxide radical scavenging activity of AgNPs was found to be increased with increasing concentrations and the average inhibition was about 62.9% as compared to the activity of plant extract. In vitro investigations on the drug delivery from AgNPs exhibited pH dependency; the release was significant (45.6%) below acidic terms (pH 5.2) when in proportion to physiological terms (pH7.4). It was observed that the resveratrol-combined to AgNPs stays on the nanoparticle surface for a lengthy time in the plasma at physiological pH (7.4), so very reducing the flank influence on the normal tissues. It can be concluded that horse chestnut leaves has reduction potential as well as being a capping agent to produce well-defined nanoscale silver particles. Our biosynthesized Ag NPs can be used antibacterial, antioxidant agent and also for as effective delivery vehicles in the near future.

  • High optoelectronic and antimicrobial performances of green synthesized ZnO nanoparticles using Aesculus hippocastanum
    Environmental Chemistry Letters, 2017
    Co-Authors: Hakan Çolak, Ercan Karaköse, Fatih Duman
    Abstract:

    Nanosized materials are of increasing interest due to their optical and electrical properties. In particular, the semiconductor ZnO has a wide band gap of 3.3 eV, which is abundant in nature and is eco-friendly. Green synthesis of nanomaterials is simple, non-toxic and adapted to large-scale production. Here we synthesized ZnO nanoparticles using the fruit shell extract of horse chestnut, Aesculus hippocastanum . ZnO nanoparticles were characterized by X-ray diffraction (XRD) and field emission-scanning electron microscopy. XRD patterns were indexed on the basis of an hexagonal structure, and the pattern indicates high crystalline quality with very well-defined high intensity peaks. The grain sizes ranged between 50 and 100 nm. Ultraviolet–visible data show that ZnO nanoparticles have a high optical transparency of 70–86%. In addition, the bactericidal effect of ZnO nanoparticles was observed against Bacillus thuringiensis .

  • erratum to high optoelectronic and antimicrobial performances of green synthesized zno nanoparticles using Aesculus hippocastanum
    Environmental Chemistry Letters, 2017
    Co-Authors: Hakan Çolak, Ercan Karaköse, Fatih Duman
    Abstract:

    Nanosized materials are of increasing interest due to their optical and electrical properties. In particular, the semiconductor ZnO has a wide band gap of 3.3 eV, which is abundant in nature and is eco-friendly. Green synthesis of nanomaterials is simple, non-toxic and adapted to large-scale production. Here we synthesized ZnO nanoparticles using the fruit shell extract of horse chestnut, Aesculus hippocastanum. ZnO nanoparticles were characterized by X-ray diffraction (XRD) and field emission-scanning electron microscopy. XRD patterns were indexed on the basis of an hexagonal structure, and the pattern indicates high crystalline quality with very well-defined high intensity peaks. The grain sizes ranged between 50 and 100 nm. Ultraviolet–visible data show that ZnO nanoparticles have a high optical transparency of 70–86%. In addition, the bactericidal effect of ZnO nanoparticles was observed against Bacillus thuringiensis.

Jana Nejmanova - One of the best experts on this subject based on the ideXlab platform.

  • residues of diflubenzuron on horse chestnut Aesculus hippocastanum leaves and their efficacy against the horse chestnut leafminer cameraria ohridella
    Pest Management Science, 2006
    Co-Authors: Josef Mertelik, Jana Nejmanova, Josef Cvacka, Ivan Hrdy, Jelena Kuldova, Alexander Muck, Petra Nesnerova, Ales Svatos
    Abstract:

    Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre−1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high-performance liquid chromatography on an octadecyl-modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long-term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimic, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry

Glynn C Percival - One of the best experts on this subject based on the ideXlab platform.

  • phosphite induced suppression of pseudomonas bleeding canker pseudomonas syringae pv aesculi of horse chestnut Aesculus hippocastanum l
    Arboricultural Journal: The International Journal of Urban Forestry, 2015
    Co-Authors: Glynn C Percival, Jonathan M Banks
    Abstract:

    Field trials were conducted using 4-year-old horse chestnut (Aesculus hippocastanum L.) to assess the efficacy of potassium and silicon phosphite as plant protection agents against the bacterial pathogen Pseudomonas syringae pv. aesculi (Pae) the causal agent of Pseudomonas bleeding canker of horse chestnut. Phosphites were applied preventatively, i.e. before Pae inoculation of trees, and curatively, i.e. after Pae inoculation of trees, and, as both a foliar spray (FS) and root drench (RD). Application of both phosphite forms induced positive effects on plant vitality (increased leaf chlorophyll content, leaf chlorophyll fluorescence (Fv/Fm)), enhanced defensive enzyme activity (β-1,3-glucanase, peroxidase) and reduced Pae lesion size, the main proxy of Pae success or aggressiveness. Preventative rather than curative phosphite application resulted in greater reductions in Pae severity. Little significance of mode of application (FS, RD) and phosphite anion (potassium, silicon) was demonstrated indicating ...

  • the impact of horse chestnut leaf miner cameraria ohridella deschka and dimic hclm on vitality growth and reproduction of Aesculus hippocastanum l
    Urban Forestry & Urban Greening, 2011
    Co-Authors: Glynn C Percival, I Barrow, Kelly Noviss, Ian P Keary, P Pennington
    Abstract:

    Abstract The aim of this study was to evaluate the impact of horse chestnut leaf miner ( Cameraria ohridella Deschka and Dimic; HCLM) on whole-tree energy loss, growth and reproduction on mature horse chestnut trees Aesculus hippocastanum L. Electron transport (ETo) flux per cross section (CS) of photosystem II (ETo/CS) was measured on HCLM infested and insecticide treated trees located in the South of England, UK. Comparison of insecticide treated trees where no HCLM activity was recorded compared with non-insecticide controls where severe HCLM activity was recorded indicated a total energy loss of 37.2% over a growing season. The relationship between phenology, leaf mining activity and subsequent loss in leaf energy indicated that up until petal fall/initial formation of seed (April–late June) energy loss ranged from 0% to 15%. However, this energy loss was not statistically significant from controls. From late June to late September energy loss significantly declined from 16% to 98%. A positive impact of controlling HCLM activity was recorded on growth, storage and reproduction. Average seed weight, seed germination and relative growth rates of germinated seedlings were 90.5, 47.6 and 35.2% higher respectively compared to trees where HCLM activity was not controlled. In addition, stem extension, root carbohydrate concentration and twig starch content values were 85.0, 33.3 and 1719.0% higher in trees where no leaf miner activity was recorded. Results indicate that while mature horse chestnuts produce sufficient energy via photosynthetic activity early in the growing season to provide energy for bud break, leaf flush and expansion and therefore maybe able to cope with repeated HCLM infestations in the long term, the impact on reproduction is of particular concern. Reduced seed weight, germination rates and seedling vigour could detrimentally impact on the long term persistence of A. hippocastanum in the UK.

  • triazole induced drought tolerance in horse chestnut Aesculus hippocastanum
    Tree Physiology, 2008
    Co-Authors: Glynn C Percival, Kelly Noviss
    Abstract:

    We determined the influence of the triazole derivatives paclobutrazol, penconazole, epixiconazole, propiconazole and myclobutanil on the drought tolerance and post drought recovery of container-grown horse chestnut (Aesculus hippocastanum L.) saplings. Myclobutanil neither conferred drought resistance, as assessed by its effects on a number of physiological and biochemical parameters, nor affected growth parameters measured after recovery from drought. Chlorophyll fluorescence (F(v)/F(m)), photosynthetic rates, total foliar chlorophyll and carotenoid concentrations, foliar proline concentration and superoxide dismutase and catalase activities were consistently higher and leaf necrosis and cellular electrolyte leakage was lower at the end of a 3-week drought in trees treated with paclobutrazol, penconazole, epixiconazole or propiconazole than in control trees. Twelve weeks after drought treatment, leaf area and shoot, root and total plant dry masses were greater in triazole-treated trees than in control trees with the exception of those treated with myclobutanil. In a separate study, trees were subjected to a 2-week drought and then sprayed with paclobutrazol, penconazole, epixiconazole, propiconazole or myclobutanil. Chlorophyll fluorescence, photosynthetic rate, foliar chlorophyll concentration and catalase activity over the following 12 weeks were 20 to 50% higher in triazole-treated trees than in control trees. At the end of the 12-week recovery period, leaf area and shoot, root and total plant dry masses were higher in triazole-treated trees than in control trees, with the exception of trees treated with myclobutanil. Application of triazole derivatives, with the exception of myclobutanil, enhanced tolerance to prolonged drought and, when applied after a 2-week drought, hastened recovery from drought. The magnitude of treatment effects was in the order epixiconazole approximately propiconazole > penconazole > paclobutrazol > myclobutanil.

Ales Svatos - One of the best experts on this subject based on the ideXlab platform.

  • residues of diflubenzuron on horse chestnut Aesculus hippocastanum leaves and their efficacy against the horse chestnut leafminer cameraria ohridella
    Pest Management Science, 2006
    Co-Authors: Josef Mertelik, Jana Nejmanova, Josef Cvacka, Ivan Hrdy, Jelena Kuldova, Alexander Muck, Petra Nesnerova, Ales Svatos
    Abstract:

    Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre−1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high-performance liquid chromatography on an octadecyl-modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long-term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimic, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry

Petra Nesnerova - One of the best experts on this subject based on the ideXlab platform.

  • residues of diflubenzuron on horse chestnut Aesculus hippocastanum leaves and their efficacy against the horse chestnut leafminer cameraria ohridella
    Pest Management Science, 2006
    Co-Authors: Josef Mertelik, Jana Nejmanova, Josef Cvacka, Ivan Hrdy, Jelena Kuldova, Alexander Muck, Petra Nesnerova, Ales Svatos
    Abstract:

    Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre−1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high-performance liquid chromatography on an octadecyl-modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long-term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimic, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry